Ok, too point a few things out
Galaxy & Akira
The Galaxy was put in service in 2357, while the Akira appeared in 2368 (This is cannon fact

)
The Nebula isnt a science vessel (not sure why I said that) it was mainly used for Exploration missions, but was refitted in light of the Cardassian border wars
The Sovereign is more powerful than the Galaxy as it was built nearly 30 years later, but not many were built, and the Sovereign was built mainly for defensive purposes (The defiant class was mainly for offensive purposes in the Dominion war and defensive purposes against the Borg)
**Sidenote: Is it possible to make the pulse phaser do more damage against the borg like in the series, or doesnt SEIV allow for this?**
As for other races, the only ship that I believe is out of place concerning size and age is the Romulan Warbird as it was built before the TNG era, just it has been upgraded time and time again
As for mounts, you could do wot you did wit the defiant cloaking mount, have certain components real expensive and each ship have its own mount so it would fit in the timeline of technology (Would be willing too do all the mounts for all the races)
As for number of ships for the Feds, from the TNG era up, I can put in 18 ships
That would be 3 carriers, 3 Transports, and 12 normal ships which can of course be reduced to a desired number
As for other races, regardless you have too start making them up, as only so much is known
But regardless of wheather you decide to go along wit this or not, I request you bring in the Prometheus class for the Feds, hell I beg you too, as that is my favourite vessel beside the Nebula
[ February 17, 2004, 03:21: Message edited by: DeadZone ]